<!doctype html>
<html lang="en">

<head>
  <title>WebGL Demo</title>
  <meta charset="utf-8">
  <link rel="stylesheet" href="./webgl.css" type="text/css">
</head>

<body>
  <canvas id="glcanvas" width="640" height="480"></canvas>
</body>

<script>
  //
  // Start here
  //
  function main() {
    const canvas = document.querySelector('#glcanvas');
    // Initialize the GL context
    const gl = canvas.getContext('webgl');

    // If we don't have a GL context, give up now
    // Only continue if WebGL is available and working

    if (!gl) {
      alert('Unable to initialize WebGL. Your browser or machine may not support it.');
      return;
    }

    // Set clear color to black, fully opaque
    gl.clearColor(0.0, 0.0, 0.0, 1.0);
    // Clear the color buffer with specified clear color
    gl.clear(gl.COLOR_BUFFER_BIT);
  }


  window.onload = main;
</script>

</html>